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Pertronix burning sparkplugs

"I`m looking for a voltage lea

"I`m looking for a voltage leak? When engine is running at idle (800rpm)or a bit higher(under 2000) with or without the gear in place, it stumbles. It can run without a stumble for awhile but then it start that stumble again. It`s the same with points and condenser too but with points and condenser the stumble isn`t so "hard". Thats why I don`t think it`s the carb. that is having some problem because the stumble would likely be as "hard" what ever ignition type I`m having right?"
 
"You do not Ohm-test for a vol

"You do not Ohm-test for a voltage leak.
Do You still use the B+ feed from the alternator?
If so,note that that is a resistor cable if not mistaken, replacing an external resistor on the coil.
Hook your meeter up on coil+ and ground set at 24Volt or similar, then run and see if voltage fluctuates when the engine starts to 'stumble'.
If is 'fluctuates' then start by disconnecting the grey from coil to tach. Shorted tachs have played a lot of games with me!"
 
I have tryed to disconnect the

I have tryed to disconnect the tach wire with no success. It drops voltage when it stumbles. The pertronix is feeded from a terminal at the alternator with an output of approx 12v.
 
What comes to the spark plugs

What comes to the spark plugs they all now look the same. Kind of white coloured but looking like they have burned the gas well (maybe running a bit lean).
 
"The output from alternator is

"The output from alternator is not the interesting part, but the input to coil?
Measure both engine running and not running!"
 
"What about the ESA in all of

"What about the ESA in all of this, after re-reading your original post I was never too sure if you had replaced it with a newer one like CDI/Rapir or if you had installed the Pertronix diode fix? Anyway, what about pulling the ESA wire off the neg side of the coil?"
 
"Morten. The feed to coil+

"Morten. The feed to coil+ is approx. 12v with ignition ON, no resister in line.
Bob. I use the diode fix. I have disconnected the ESA with no better result."
 
"Run it until You get the prob

"Run it until You get the problem, and keep the meeter hooked up. The only way to be sure You do not have a voltage fluctuation. It might even be caused by the alternator regulator.
An alternative is to make a separate test jumper wire straight from Bat+ to coil for test and see if problem disappears."
 
I had the volt meter connected

I had the volt meter connected and the voltage was dropping like it drops on the voltmeter at the dash.I have tested to feed the coil+ straight from battery+ with no success. Still stumbles.
 
"'I had the volt meter con

"'I had the volt meter connected and the voltage was dropping like it drops on the voltmeter at the dash.'????
What do You mean by that??
If possible, borrow a timing light with built in tach, hook it to each and one of the plug cables and test. (You may even use a Fluke Clamp meter and put it on Hz).
Are You loosing sparks?
If loosing, even test the lead from center coil to dist-cover!"
 
"I ment that when the engine s

"I ment that when the engine stumbles, the volt meter at the dashboard is dropping voltage. The same is showing on the multimeter when it`s connected between coil+ and ground. When it stumbles I can hear rpms dropping.
What do I need that timelight with built in tach to? Can I just test the spark plug cables with a timing light."
 
"Now You are making it 'di

"Now You are making it 'difficult'.
When the engine 'stumbles', voltage drops?
But if You are running a steady B+ jumper from battery to coil, how does the voltage drop?
May it all be a question of a faulty contact in the extension cable between engine and instruments?
Do if possible a test using a separate fully charged battery on coil/ign only!(isolate ign from the rest of the engine electrical)
I just find it easier to work with a timing light with built-in tach, gets more precise.Used to have one with tach and dwell, adjustable 2/4 stroke as well. Watching a blinking light is in the long run like watching an arch welder - You get blind!"
 
Ok. But how do I wire it? I ha

Ok. But how do I wire it? I have my previous battery and I could charge it full and try with that but...the wiring?
 
"try removing B+ lead(

"try removing B+ lead(s) from coil and tape up.

Connect isolated battery - to engine block via jumper wire.

connect battery B= to coil + via jumper wire. (Use any existing ballast resistor, if installed.)

Start engine and see what happen. If stumble is eliminated w/ isolated battery, you have a harness/switch/connector issue. If stumble still present, you have an issue within the ignition system."
 
"PROBLEM SOLVED?
I tested it


"PROBLEM SOLVED?
I tested it with an external battery to run the ignition side by it self, with no success.
When I was checking the clamps, I was pretty near the alternator and the coil with my head and I heard a "tick" like a small spark. I listened some more and then again "tick". When I heard the "tick" the engine stumbled. Then I saw it (the spark). The shell from the coil gave a spark to the clamp that holds the coil. I had put a rubber in the clamp to isolate the coil but it was too narrow. It gave 1/2" long spark. I disconnected the coil and hang it up on a piece of rope and started the engine. NO PROBLEMS anymore (I think). When i touched the coil when the engine was running I got small electrical shocks from the shell. I run it for about 1/2 hour in the dock and it seems ok. I`m putting a wider rubber to isolate the coil.I`m soon going for a 2 hour test ride with it. Wish me luck.
Thanks guys for all replys and ideas."
 
"Is the coil 'lying' d

"Is the coil 'lying' down or 'standing'?
If an oil-filled coil it has to be mounted vertical!
Double check the mounting instruction for the coil you have got. If an epoxy filled coil, it may be mounted horizontal.
Anyway, this sounds promising."
 
"The only possible way to get

"The only possible way to get a spark jump to ground from the coil is then normally if the rubber boot on the center cable going to distributor is not isolating properly. It may be too short, it may have been sprayed with WD40 or similar, or the flame thrower coil demands special plug leads."
 
"Try some silicone dielectric

"Try some silicone dielectric grease in the high tension lead's 'tower' of the coil. If you don't have any, ask the professional electrician friend to get some for you.

It would be a good idea to add that grease to your spark plug lead boots, too. It is excellent for preventing high voltage leaks. Its only drawback is finite lifetime - it needs to be renewed every year or so."
 
"I installed the coil back in

"I installed the coil back in with 0,08" thick rubber between coil and bracket and it sparked thru that (I think) because it was stumbling again. I`m going to install the coil to the "engine compartment wall" and try with that."
 
"[b]"that coil is cracked

""that coil is cracked somewhere."
Yep....... You need to get that bomb out of your boat.
uhoh.gif

And put this thread to rest..
whistle.gif
"
 
So the coil is cracked used un

So the coil is cracked used under 15 hours. It`s out of warranty because I bought and installed it in the winter. What coil should I put there? Hipower 45.000v.? Should I put in some resistors in line for the current feed to the coil+ ? Is it the coil that needs the resistors or what?
Thanks.
 
"I would have gone back to you

"I would have gone back to your local distributor and claimed warranty, unless the coil has external damage from being dropped.
Another option might be to contact Pertronix direct from their web page."
 
"If I understand it correctly,

"If I understand it correctly, I should have a resistance of 3ohm total? Why didn`t I buy a 3 ohm coil in the first place? I think it`s because pertronix told me I could run straight a 0,6ohm coil without any other resistance wires/blocks. With the new coil I`m going to buy, I`m going to put that 3ohms resistance and see how it affects the engine.
I took the flame thrower II coil off the engine and tryed it out with my oem coils, I have 2 of them. Still stumbling. It`s missing spark now and then, I checked with a timing light.
I thougt I had found the problem but it seems to be haunting me."
 
"Typically the OEM coils were

"Typically the OEM coils were 1.5 and the resistance wire was approx 1.4-1.5 to give you a total of 3, the hi-perf coils are less which gives you the hotter spark (higher voltage), not sure why you would still be stumbling once you swapped out the coil, sure seemed like you had found the problem. Can you hear any spark jumping now when it stumbles, bad coil hi-voltage wire?"
 
"No jumping sparks anymore wit

"No jumping sparks anymore with the lower voltage coils. I tryed with new hi-voltage wires and it made no difference. With the timing light hooked up on the wires I could see that it misses sparks. This was on every cylinder, had it running for about 30 mins. and tested.
It`s like the ignitor don`t give a signal every time like it should. I got a new one at warranty because I suspected a fail in the ignitor.
In my opinion there shouldn`t be anything electrical in the dist. eccept for the rotor + dist. cap + ignitor and a good ground to dist. body, am I right? Or could there be a failure in the dist.?"
 
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